The roof on my house was replaced several months ago, right before I bought it. The realtor told me that moisture had come through the wall, and they realized it was a leak in the roof, which was then replaced. I've been replacing the baseboards throughout the house, and when I removed the baseboard below where the leak had been, I found mold: As you can see, it's on both sides of that small protruding wall that comes out from the exterior wall. Do I need to tear all that down and see how extensive it is? Should I just assume it's a big problem and hire someone to take a look at it?